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Title: XPS and SIMS study of the surface and interface of aged C + implanted uranium

Abstract

X-ray photoelectron spectroscopy in combination with secondary ion mass spectrometry depth profiling were used to investigate the surface and interfacial chemistry of C + ion implanted polycrystalline uranium subsequently oxidized in air for over 10 years at ambient temperature. The original implantation of 33 keV C + ions into U 238 with a dose of 4.3 × 10 17 cm –3 produced a physically and chemically modified surface layer that was characterized and shown to initially prevent air oxidation and corrosion of the uranium after 1 year in air at ambient temperature. The aging of the surface and interfacial layers were examined by using the chemical shift of the U 4f, C 1s, and O 1s photoelectron lines. In addition, valence band spectra were used to explore the electronic structure of the aged carbide surface and interface layer. Moreover, the time-of-flight secondary ion mass spectrometry depth profiling results for the aged sample confirmed an oxidized uranium carbide layer over the carbide layer/U metal interface.

Authors:
 [1];  [1];  [1]
  1. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1325862
Report Number(s):
LLNL-JRNL-689488
Journal ID: ISSN 0734-2101; JVTAD6
Grant/Contract Number:
AC52-07NA27344
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films
Additional Journal Information:
Journal Volume: 34; Journal Issue: 6; Journal ID: ISSN 0734-2101
Publisher:
American Vacuum Society
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; uranium; surface oxidation; X-ray photoelectron spectroscopy; carbides; ion implantation

Citation Formats

Donald, Scott B., Siekhaus, Wigbert J., and Nelson, Art J. XPS and SIMS study of the surface and interface of aged C+ implanted uranium. United States: N. p., 2016. Web. doi:10.1116/1.4962386.
Donald, Scott B., Siekhaus, Wigbert J., & Nelson, Art J. XPS and SIMS study of the surface and interface of aged C+ implanted uranium. United States. doi:10.1116/1.4962386.
Donald, Scott B., Siekhaus, Wigbert J., and Nelson, Art J. 2016. "XPS and SIMS study of the surface and interface of aged C+ implanted uranium". United States. doi:10.1116/1.4962386. https://www.osti.gov/servlets/purl/1325862.
@article{osti_1325862,
title = {XPS and SIMS study of the surface and interface of aged C+ implanted uranium},
author = {Donald, Scott B. and Siekhaus, Wigbert J. and Nelson, Art J.},
abstractNote = {X-ray photoelectron spectroscopy in combination with secondary ion mass spectrometry depth profiling were used to investigate the surface and interfacial chemistry of C+ ion implanted polycrystalline uranium subsequently oxidized in air for over 10 years at ambient temperature. The original implantation of 33 keV C+ ions into U238 with a dose of 4.3 × 1017 cm–3 produced a physically and chemically modified surface layer that was characterized and shown to initially prevent air oxidation and corrosion of the uranium after 1 year in air at ambient temperature. The aging of the surface and interfacial layers were examined by using the chemical shift of the U 4f, C 1s, and O 1s photoelectron lines. In addition, valence band spectra were used to explore the electronic structure of the aged carbide surface and interface layer. Moreover, the time-of-flight secondary ion mass spectrometry depth profiling results for the aged sample confirmed an oxidized uranium carbide layer over the carbide layer/U metal interface.},
doi = {10.1116/1.4962386},
journal = {Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films},
number = 6,
volume = 34,
place = {United States},
year = 2016,
month = 9
}

Journal Article:
Free Publicly Available Full Text
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